CYPERACE/E. 433 



CYPERACE/E. 



Sedge. 



Sedges are distinguished from grasses by the 

 stem being sob'd and usually triangular, the leaves in 

 three not two vertical rows, with a complete sheath at 

 the base (not split down the opposite side) and 

 without ligule; and (though the flowering portion 

 being made up of spikelets may appear at first sight 

 similar) by the absence of the paleas and lodicules, 

 and by an ordinary straight embryo in the triangular 

 nut, the cotyledon of which does not stay inside on 

 germination. 



They are as a rule found only in marshy places, 

 and have a perennial creeping stem (rhizome) and grass- 

 like flowering stems and leaves, which however are 

 devoid of starch and sugar and so useless as fodder 

 The flowers are exceedingly simple, and consist of an 

 ovary with single, trifid or bifid, style, surrounded by 

 two or three stamens, whose anthers are not versatile, 

 but attached by their bases. There are often also 

 three to six bristles which are regarded as representing 

 the lost perianth. Each such flower is in the axil of a 

 bract, called the glume ; and the glumes are arranged 

 in short or long spikelets the lowest glumes being often 

 empty. In CAREX a complication is introduced by the 

 presence of a casing round the ovary, and the "flowers" 

 are unisexual. But this is referred to under the genus. 

 The axis of the spikelet is called the rachilla. 



The family comprises some 3,000 species, in 60 genera, and 

 is found all over the world, mostly in damp and sour ground. 

 Like the Grasses they are commonly gregarious, and pollinated 

 by wind. 

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